My periodic table poster is now available! Terfenol magnetostrictive alloy. Terfenol is a material that changes shape in response to a magnetic field. It is used in a commercial product called a SoundBug, which turns any solid surface into a speaker (by vibrating it using a slug of terfenol, of course). We use a SoundBug to project sound out of the beautiful periodic table display that Max Whitby and I recently installed at DePauw University. Of course the SoundBug is mounted against the inside face of the terbium cube, so the sound appears to be coming from the general area of terbium. These are a couple of spare slugs the SoundBug company sent us to include in the DePauw and future displays. Source: Max Whitby of RGB Contributor: Max Whitby of RGB Acquired: 1 November, 2003 Text Updated: 6 February, 2008 Price: Donated Size: 0.75" Purity: <50%